A series summation method for the determination of voltage ratios at power frequency with high accuracy

The principle of a new series summation method is presented. The ratio standard is a 1-kV inductive voltage divider. The divider can be self-calibrated with an uncertainty of 0.3 p.p.m. using the reference voltage method. The voltage ratio error variation provided a voltage dependence error curve. The uncertainty of the 1-12-kV curve and the 10-80-kV curve is 5 p.p.m.. In two steps, 110 kV/ square root 3 can be obtained, and, compared with the parallel-series setup method of 12 p.p.m., the new method yields 10 p.p.m.<>